Magnetic separator.



- G. ROWAND. MAGNETIC SEPARATOR. APPLICATION FILED JAN.27, 1903. RENEWEDDEC. 12, 1912.

v Patented July 29, 1913.

9 SHEETS-SHEET 1.

L. G. ROWAND.

MAGNETIC SEPARATOR.

. APPLICATION FILED mzmv, 190s. RENEWED DEO.12, 1912. 1,068,453..

Patented July 29, 1913.

9 SHEETS-SHEET 2.

Wiliwfiesg /WQM O.

L. G. ROWAND. MAGNETIC SBPARATOR. APPLICATION FILED JAN.27, 1903.RENEWED DEC. 12, 1912.

'1 68,453, Patented July 29, 1913.

9 SHEETS-SHEET 3. i

L. G. ROWAND. MAGNETIC SEPARATOR. 1 APPLICATION FILED mum-z, 190s.RENEWED DEC. 12, 1912.

Patented July 29, 1913.

9 SHEBT8-SHEET 4.

L. G. ROWAND.

MAGNETIC SEPARATOR. APPLICATION FILED JAN.27, 1903. RENEWED DEO.12,1912. '1 ,068,45

Patented July 29, 1913.

9 S HBETFSHEET 6.

L. G. ROWAND. MAGNETIC SEPARATOR.

APPLIGATIONIILBD JAN.27, 1903. RENEWED DEC]. 12, 1912.

Patented July 29, 1913.

9 SHEETS-SHEET 6.

L. G. ROWAND.

v MAGNETIC SEPARATOR. APPLIOATION FILED $1111.27, 1903. RENEWED DBO. 12,1912.

"1 ,U68,%5. 1 Patented July 29; 1913.

9 SHEETS-SHEET 7.

L. G. ROWAND.

MAGNETIC SEPARATOR. I APPLICATION FILED JAN.27, 1903. RENEWED DEC. 12,1912.

Patented July 29, 1913.

I 9 SHEETS-SHEET 8.

L. G. ROWAND. V MAGNETIC SEPARATOR. APPLICATION FILED JAN.27, 1903.RENEWED D110. 12, 1912.

1,068,450 v Patented Ju1 29,1913.'

9 SHEETS-SHEET 9.

ii ans r'rnr OFFJIQ.

LEWIS G. ROWAND, OF EAST ORANGE, NEW JERSEY, ASSIGNOR TO WETHERILL SEPA-i RATING COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

MAGNETIC SEPARATOR.

To all whom it may concern Be it known that I, Lewis G. ROWAND, acitizen of the United States, residing at East Orange, county of Essex,State of New J ersey, have invented certain new and useful Improvementsin Magnetic Separators; and I do hereby declare the following to be afull, clear, and exact description of-the invention, such as willenable-others skilled in the art to which it appertains to make and usethe same.

. nally. Along the neutral line or plane re ferred to, the magnetism ispractically m'l, and I make use of this factor, in some forms ormodifications of the apparatus, to clear the armature thereat of theattracted particles, without having recourse to auxiliary brushes orcleaning-belts. The gradual decrease in the intensity of magnetizationfrom v the line or plane of highest magnetization to the neutral line orplane, may also be made available for obtaining a number of fractionalseparations into heads of difierent magnetic permeabilities, as willhereinafter more fully appear.

Generically considered, my invention is applicable to the separation ofmaterials of high magnetic permeabilityfsuch as magnetite, and also tothe separation of materials of such low magnetic susceptibility thatthey can only be successfully treated in accordance with the well knownWetherill process of'magnetic separation.

-My invention is also applicable to both wet and dry separation, some ofits most advantageous forms being designed to separate, either in thedry way or in the wet way, materials of extremely low magneticpermeability or susceptibility.

In the accompanying drawings, Figure 1 represents a plan view of thefield of magnets and armatures of a magnetic separator constructed inaccordance with one form or modification of my invention; Fig. 2 represents, on a somewhat larger scale and partly Specification of LettersPatent.' H Patgntedl July 29, 11913. Application filed January 27,1903', Serial No. 140,689.

Renewed December 12, 1912. Serial No. 736,402.

in section, a suitable construction of armature for the purposes of theinvention; Fig. 2 is a similar view showing a modified form of thearmature; Fig. 3 represents a sectional elevation of a magneticseparatorconstr ucted. in accordance with oneform or modification of theinvention; Figs. 4, 5, 6 and 7 represent like views of other forms ormodifications thereof; Figs. 8 and 9 represent like views of magneticseparators constructed in accordance with my invention and adapted tosubject the tailings to a second separation; Figs. 10 and 11 representlike views of magnetic separators constructed in accordance with myinvention and adapted to subject the heads to a further separation Fig.12 represents a sectional elevation of a magnetic separator constructedin accordance with my invention and adapted particularly to thetreatment of materials of low magnetic permeability; and Fig. 13 is alike view of a magnetic separator constructed in accordance with myinvention and designed particularly to treat material of low magneticpermeability in the wet way.

Similar letters of reference. indicate similar parts throughout theseveral views.

, As hereinbefore indicated, the essential or characteristic feature ofthe invention consists in subjecting the material to be separated to theaction of an armature rotating in a magnetic field, in such mannerthat,with respect to a neutral line or plane dividing the armaturelongitudinally, magnetisms of opposite signs are developed in thearmature, the intensity of the magnetization diminishing gradually froma plane of highest magnetization to the neutral plane referred to. Thearmature is so related to the magnetic poles, that the armature aloneserves as the separating element.

As shown in Fig. 1, the magnetic field may conveniently consist ofopposite pole pieces a, 6, either or both of which may be energized by asuitable coil or coils A, B, and which may have two air gaps as shown,so as to double the capacity of the apparatus for separating purposes.If but one coil, (as, for instance, A), is used, the opposing polepieces 6 will nevertheless serve as keepers and conductors of themagnetic flux or circuit through the armatures. If both coils A, B, areemployed, it will, of course,

"be understood that they must be so wound but one co-il wereemployed.

The rotatory armature, as shown in detail in Fig. 2, is laminated. Thismay be conveniently done by mountin upon the shaft 0 a series of metaldisks separated by intervening spaces. These spaces may be occupied by acorrespondin series of disks 6 of insulating material, W ich preferablyextend to the outer periphery of the armature as a whole. The series ofdisks are compressed and held together by the end collars f, therebycompleting the structure. It will be evident, however that, from amagnetic standpoint, a similar result will be obtained by providing asolid metal cylinder (see Fig. 2) with a series of transverse annulargrooves d, leaving intervening ridges which m'ay,'thereafter, be filledwithnon-magnetic material, as, for instance, brass, lead, or the like.The feature of laminating or grooving the armature is of particularservice for the reason that it prevents the overheating of the armaturedue to the production of eddy currents, and also for the reason that theedges of the magnetic laminae, or of the magnetic ridges between thenon-magnetic filling, present areas of higher concentration of themagnetic lines of force than would be, afl'orded by an unbrokencylindrical magnetic surface, as will be readily understood.

For material of high magnetic perme ability or susceptibility, such asmagnetite, I prefer to employ the feeding devices shown in Figs. 3 to10. These feeding devices consist of a hopper D, provided at itsdischarge end with the feed regulating roller E and the movable gate 9(said gate being shown in Fig. 3). The material from the hopper isdistributed by the roller E through the vertical chute F. At the base ofthe chute is located the rotatory armature or armatures C, andit isdesigned that the speed of rotation of the armature shall be slightly inexcess of the velocity of the falling material as it passes the saidarmature. In Fig. 3, the magnetizable particles or heads are attractedby the armature C and are deposited in the receptacle H, whereas thenon-magnetic particles or tailings pass on into the receptacle G, anadjustablewing or gateh determining, by its position, the completenessof the separation. The rotation of the armature is foundfin practice, tohave a fan suction action, to some extent, upon the falling material,and consequently tends to some degree at least, to draw some of thefiner non-magnetic dust into the receptacle H. To obviate thisinconvenience, I sometimes find it desirable to provide both of thereceptacles G and H with automatic valves" or gates 2', at theirdischarge ends, and to provide the receptacle G with an exhaust pipe 7',wherein is maintained an exhaust sufficient to neutralize the fan actionof the armature C. I also prefer to provide the magnetic separator shownin Fig. 3 and in some of the remaining figures, with a partition plate kof rubber, or the like, for the purpose of intercepting any particleswhich might otherwise be carried beyond the neutral line or plane bycentrifugal force, and which would otherwise bombard the pole piece andtend to wear it away. In the construction shown in Fig. 4:, the samecharacteristic features are preserved with the exception that, insteadof the partition plate In, I employ an endless apron Z, whicheffectually protects the pole piece against the bombardment re- 35referred to. In the construction shown in Fig. 5, the same features arepresent as in Fig. 4, with the exception that the interpolar spacecontains two armatures instead of one,

the heads being received in the outer 9o receptacles H, H and thetailings in the central receptacle G. The construction shown in Fig. 6is identical with the construction shown in Fig. 5, with the omission ofthe belts Z in said latter figure, and the substitution therefor of theintercepting partitions. The construction shown in Fig. 7 is identical,inso far as'the rotatory armatures and magnets are concerned, with theconstruction shown in Fig. 6, but the material is fed between therotatory armatures and the pole pieces, and the armatures rotate in suchmanner that the heads are received in the central receptacle H and thetailings in the outer receptacles or chutes -G',-.G In Fig. 9, I haveillustrated an arrangement whereby the tailings from a separator of thetype shown in Fig. 7, are subjected to the further separating action ofanother separator of the same type, said tailings finally passing intothe chutes or receptacles G G while the heads are collected in thereceptacles H, H In Fig. 8, I have illustrated the manner of employingtwo separators, of the type shown in Fig. 3, for subjecting the tailingsto a second separation, the heads being finally received in thereceptacle or chute H and the tailings in the receptacle or chute G InFig. l0,

I have shown the manner of employing two separators, of the type shownin Fig. 3, for subjecting the heads to a second separation, the headsbeing finally received in the recep: tacle or chute H and the tailingsinthe receptacle or chute G.

In Fig. 11, Ihave shown the'application of two separators, of the typeshown in Fig, 7, for the purpose of subjecting the heads to a secondseparation, the heads being finallyreceived in the chute ,or receptacleH and the tailings being received in the .tates in the directionindicated by the arseveral chutes or receptacles G G G G Theconstruction and mode of operation of these arrangements for subjectingeither the heads or tailings to further separation, is so fully shown inthe drawings that further description thereof is unnecessary.

For the treatment of materials of low magnetic susceptibility, I prefertheseparators shown in Figs. 12 and 13. In F ig. 12, the material to betreated is fed from the hopper D directly upon the armature C, whichrotates in the direction indicated by the arrow, the pole pieces beingformedas shown so as to obtain a high concentration of the magneticlines of force. The tailings" are received in the chute or receptacle G,the first heads in the receptacle H and the second heads in thereceptacle H, the movable gates or shutters determining the character ofthe heads received in the two compartments. This fractional separationof the heads is made possible for the reason that the magnetic materialis discharged at difierent points, according to the relative magneticpermeability of the constituents of said material. The magneticintensity of any particular part of the armature gradually decreases asthat part approaches the neutral axis; so that the particles ofrelatively lower magnetic permeability fall off first, whereas those ofrelatively stronger magnetic permeability continue to adhere to thearmature and are liberated near the neutral point, where the armaturechanges polarity and where the attractive force is practically m'Z. .Byvarying the speed of rotation of the aramture, the angle of deflectionbetween the stream of the falling non-v magnetic particles and themagnetic particles may be widened, but there is a practical limit tothis increase of angular velocity of the armature, because of the factthat the centrifugal force developed tends to throw off the weaklymagneticmaterial. While I have shown the apparatus of Fig. 12 as appliedto the separation of dry magnetic material, yet it is also applicable tothe separation of wet magnetic material provided that the armature andmagnet poles, together with the receiving receptacles, are immersed in awater tank. In Fig. 13, the magnetic separator shown is designedparticularly for wet separation, and especially for the separation ofwet pulp or similar fine material, which could not be so well separatedin a wet way by the apparatus shown inrEig. 12. The pulp is suppliedfrom the hopper D to the incline m, and is delivered upon the surface ofthe armature C which rorow, i. e. in an opposite direction to thedirection of rotation used in the apparatus of Fig. 12. The magneticconstituents of the pulp are attracted and held by the rotatingarmatureand are conveyed upward'and over the highest point of thearmature, while the non-magnetic tailings flow down the feed side of.the roller. At or near the lowest point of the armature, and at aboutthe neutral line or plane thereof, the partition Z2, provided with alightelastic strip of rubber or the like, bears slightly againstthearmature, thus preventing any portion of the heads from being carried oninto the tailings receptacle. To freethe magnetic pulp from anynon-magnetic material mechanically carried along or entangled therewith,a spray pipe 72, or the like, is provided just above the point of feed,so as to wash out such tailings with water and carry them down into thetailings receptacle G. The heads are received, as indicated, in theheads receptacle H What I claim is 1. A magnetic separator, providedwith a field magnet, having opposing pole pieces, a rotatory armaturelocated in the interpolar gap and in inductive relation to the polepieces, a gravity feed for dropping the material to be separated inproximity to the armature, said vgravity feed consisting of an upperhopper and feed roller, and a vertical chute leading therefrom andsubstantially tangent at its lower portion to the rotatory armature, andmeans for driving the armature at a speed greater than the velocity ofthe falling material and in the same direction therewith, .substantiallyas described.

2. A magnetic separator, provided with a field magnet having. opposingpole pieces, a rotatory armature located in the interpolar gap, agravity feed for dropping the material to be separated in proximity tothe armature, and means for driving the armature at aspeed greater thanthe velocity of the falling material and in the same direction therewithsubstantially as described.

3. A magnetic separator, provided with a field magnet having opposingpole pieces, a pluralityof rotatoryarmatures located in the interpolargap, a gravity feed for dropping material to be separated between thearmatures, and means for driving the armatures at speeds greater thanthe velocity of the falling material and in the same directiontherewith; substantially as described.

4. A magnetic separator, provided with a field magnet having opposingpole pieces, a plurality of rotatory armatures located in the interpolargap and in inductive relation to the pole pieces, a gravity feed fordropping material to be separated between the armatures, said gravityfeed consisting of an upper hopper and feed roller, and a vertical chuteleading into the interpolar space between the armatures, and means fordriving the armatures at speeds greater than the velocity of the fallingmaterial and in the same direction therewith; substantially asdescribed.

5. In a magnetic separator, the combination with a magnet, of poles ofopposite polarity on said magnet, a substantially horizontal shaftmounted to revolve between said poles, an armature placed upon saidshaft, permeable projections on said armature, means for feedingmaterial to be separated between one of said poles and said armature,and means for revolving said armature.

6. In a magnetic separator, the combination with an axiallyrotatablecylindrical; armature having permeable project-ions thereon, ofmagnet-poles- -external to said armature facing the same in suchposition rated between the last mentioned pole and cylinder.

7 In a magnetic separator, the combina tion of poles of oppositepolarity, a substantially horizontal shaft, and an armature mountedthereon adapted to revolve between said poles, said poles being externalto said armature, inductively magnetizable projections on the surface ofsaid armature, said projections being of such shape and spaced from oneof said poles'such a distance that the material will be attracted fromsaid pole to said projection, means for rotating said armature and meansfor feeding material to be separated between said pole and the armature.

In testimony whereof I aifix my signature, in presence of two witnesses;

LEWIS G. ROWAND. Witnesses FRANZ MEYER,

GUSTAV HARTMANN.

